Wardrop's size of ore body is not obvious in the report.
The Wardrop report plans on 20,000 tonnes /day processing. I'm assuming that this is for the ore only and that waste (1.1:1) will be 22,000 tonnes/day.
If Wardrop is using the 20,000 tonnes/day ore for 343 days/year for 31 years then their calculations are based on the 214M tonne figure for Sisson at 0.069% WO3 and 0.024% Mo.
Does this sound reasonable?